Wahlbergdown

This is Wahlbergdown, a programmable version of Markdown, submitted to LangJam 0001.

This README file is actually a Wahlbergdown program!

Try running:

cargo run --release -- README.md

The next part should be "42": (+ 40 2).

Building

cargo build --release

Usage

You can do:

cargo run -- --help

for help with commands.

For running files, you do:

cargo run --release -- run <file>

(I recommend running in release, for performance)

You can also see the output of the lexer, or the parser:

cargo run -- lex <file>
cargo run -- parse <file>

You can also build the project, and put the wahlbergdown executable in your PATH, by running:

cargo install --path .

Language

From this part onwards, I'd recommend opening this markdown file in a text editor, so you can see the actual syntax. Otherwise, these explanations are going to seem very confusing.

The language takes in a markdown file as input, and spits out a markdown file as output.

You can interpolate using two ticks:

3 4 (+ 3 4)

Basic arithmetic expressions are available:

(+ 1 1 2) (- 3 1 1) (* 2 3 4) (/ 40 2 2)

Logical expressions are available as well:

(and 1 0) (and 1 1) (or 1 0) (or 0 0)

(not 1) (not 0)

You also have if expressions:

(if 1 2 3) (if 0 2 3)

You can also define values in comments:

x y (+ x y)

You can also define new functions:

(add 2 3)

These can be recursive:

(add 2 3)

Tail-recursion is detected, to avoid stack overflows:

(add-tr 1000000 2)

If you try that function with add, it will blow up :p

And, that's about it. You can also check the examples directory for more.